JPH0245008Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a thermal print head.

In this type of thermal print head, it is desirable to place the heating dots at one end of the board, so that printed characters, figures, etc. can be viewed directly immediately after printing. You can get the following advantages. However, it is necessary to connect electrical leads to the resistive heating elements that make up the heating dots, so even if you try to install the heating dots at one end of the board,
Due to problems with the installation area of the lead, it may not be possible to install the lead sufficiently close to one end.

FIG. 1 shows a conventional thermal print head of this kind, in which 1 is a substrate made of ceramic or the like, 2 is a heating dot made of a resistance heating element, and one end of the substrate 1 is 1.
They are arranged in a straight line in close proximity to each other along A and parallel to the end portion 1A. Reference numeral 3 denotes an individual lead connected to one edge (part) of each heating dot 2, which is drawn out toward the other end 1B of the substrate 1, and 4 is an individual lead connected to one edge (part) of each heating dot 2. ) is a common lead that is commonly connected to FIG. 2 shows an enlarged view of the relationship between the heating dots 2 and the leads 3 and 4.

By the way, as can be understood from the figure, when one of the leads 3 and 4 is pulled out from one edge (part) of the heating dot 2 toward the end 1A side, that lead 4 is pulled out from the other end. There are times when it is desired to route the lead 3 toward the end 1B, but in that case, the heating dot 2 must be formed inside the end 1A by an amount corresponding to the width of the lead 4, and the end I have no choice but to move away from Division 1A. In order to bring this as close as possible to the end 1A, the width of the lead 4 must be made narrower, but if this is done, the resistance value of the lead 4 will increase,
As the amount of current flowing throughout the leads 4 increases, the voltage drop becomes significantly large, which adversely affects print quality.

In order to avoid this drawback, it is possible to stop the wiring of the lead 4, and for that purpose, it is necessary to
It is sufficient to extend the leads 4 to the edge and back surface of the end portion 1A, but if the leads 4 are formed by vapor deposition (or sputtering), the edges,
The substrates must be rotated one after another so that the back side faces the deposition source. Therefore, the vapor deposition process is repeated many times, making manufacturing extremely complicated.

The object of this invention is to provide a thermal print head that facilitates the formation and routing of leads when installing heating dots sufficiently close to one end of a substrate.

An embodiment of this invention will be explained with reference to FIG. 3 and subsequent figures. Note that parts given the same reference numerals as in FIG. 1 and the like indicate the same or corresponding parts. According to this idea, one end 1A of the substrate 1 is inclined. A suitable angle of inclination is 30 to 45 degrees. A common lead 4 connected to one end of the heating dot 2 is formed on the surface thereof, extending to the edge of the substrate. This formation is performed simultaneously with the leads 3 and the like by vapor deposition or the like. However, since the end portion 1A is inclined, there is no need to turn the substrate for vapor deposition as in the conventional method. In other words, there is no need to increase the number of deposition steps. Separately, a printed circuit board 5 (including a flexible printed cable) is prepared. This has one end bent to form a bent edge 5A. Leads 6 and 6A are provided across the surface and the surface of the bent edge 5A.

The substrate 1 is placed on the surface of the printed circuit board 5.
At this time, the end portion 1A is brought into contact with the bent edge 5A.
Then, solder (or conductive paste) 7 is poured so as to span the lead 4 on the end portion 1A and the lead 6A on the surface of the bent edge 5A.
Connect. By this connection, the lead 4 is routed through the leads 6 and 6A on the printed circuit board 5, and reaches an area behind the other end 1B of the circuit board 1.

When configuring the thermal print head as described above, when the heating dot 2 is installed sufficiently close to one end of the board 1, the leads drawn out to that end are connected to the other end of the board 1. In order to route it to the end 1B side, we used the lead of the printed circuit board and routed it through the back side of the board 1, so unlike the conventional method, we used the lead by vapor deposition on the edge and back side of the board. Formation becomes unnecessary. Moreover, since the leads of the printed circuit board are used, the leads can be easily routed and the configuration is extremely simple.

As described in detail above, this invention has the effect of making it possible to route the leads with a simple structure when forming the heat generating dots on the substrate.

[Brief explanation of drawings]

Fig. 1 is a plan view of a conventional example, Fig. 2 is a partially enlarged plan view, Fig. 3 is a sectional view showing an embodiment of this invention, Fig. 4 is a plan view of the same, and Fig. 5 is a printed circuit board. FIG. 1... Board, 2... Heat generating dot, 3... Individual lead, 4... Common lead, 5... Printed circuit board, 5A... Bent edge, 6, 6A... Lead, 7...
...Solder.

Claims (1)

[Claims for Utility Model Registration] Heat-generating dots are provided on the surface of the substrate at offset positions toward one end of the substrate, and the heat-generating dots are located at one end and the other end of the substrate. In a thermal print head in which leads are pulled out from each edge of the substrate, one edge of the substrate is inclined, and a wire is formed on the surface thereof from one edge of the heating dot to one edge of the substrate. A lead that is an extension of the lead drawn out to the other side is provided, and one end of the lead is bent to form a bent edge on the surface of the printed circuit board, and one end of the board is brought into contact with the bent edge of the printed circuit board. are overlapped, and the surface of the bent edge is arranged so that the leads on the surface of one end of the board are routed through the leads on the surface of the printed circuit board to the other end of the board. A thermal print head in which the leads on the surface of one end of the board are connected by solder or the like.